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Buku Teks
Berridge, G. R, author
Palgrave Macmillan, 2015
Buku Teks
Bryar, Rosamund M., author
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Buku Teks
Dale, Ernest, author
McGraw-Hill, 1973
Buku Teks
Steward, Julian H., author
Social Science Research Council, 1950
Buku Teks